Can't vouch for the game itself but the source was useful in getting my head around some of the compiler quirks that can arise when using z88dk and assembly code with the sdcc compiler instead of sccz80.

I wrote a series of getting started articles for Z88DK earlier this year, but stopped before doing SP1. It's a rather intimidating library which is poorly documented. The docs which are there appear to be a bit out of date.

The examples and Blackstar source are probably your best bet, but learning a library by reading source code isn't easy.

@PeterJ, did you get any further with SP1? I've been looking at it for a few hours now and all I'm getting is bl**dy frustrated!

I was trying to write a simple program which would print a single sprite on the screen. Working forwards (i.e. starting with a blank editor) I just hit crashes, smudges and squiggles. So I started again with one of the demos and started taking stuff out which didn't seem relevant. I achieved my aim, but have no idea how it works!

and replacing them with a zero. I don't know what any of those do, and there's no documentation for them, so what use could they possibly be? Turns out that without them the program prints a squiggle on the left side of the screen, but I've no idea why.

I think this is building the sprite in memory, column by column. But what's the LOAD1 and LOAD1RB mean? And why the 8? Weird things happen if I take these lines out of change them.

In the graphics file the 8 zero bytes after the sprite data are required. A smudge appears next to the graphic if I leave them out. The old spritepack doc suggests they're required for mask data, or maybe rotation data. It's not really clear.

Anyway, enough of my honking. It's just frustration really. Has anyone learnt how to use SP1? If so, how did you go about it?